Integrated circuits, in particular those equipped with memories containing sensitive information, need to be protected as far as possible against attacks, in particular attacks that are designed to discover stored data.
One possible attack may be carried out by a focused beam of ions (FIB for Focus Ion Beam), for example by means of a laser beam.
The effectiveness of such an attack increases when the substrate of the integrated circuit is thinned by the attacker, from its back face, in such a manner as to come as close as possible to the components of the integrated circuit, formed on its front face.